Bacterial Infections Upregulate Cluster of Differentiation 80 on Regulatory B-Cells in Iraqi Children with Type I Diabetes Mellitus

Background: Although type 1 diabetes mellitus (T1DM) is thought to be an autoimmune ailment driven by T-cells, recent research also suggests that B-cells are important in the development of the condition. In order to maintain tolerance, regulatory B-cells restrict ongoing immunological responses and restore immune homeostasis. Objective: The current investigation aimed examined the expression and mean fluorescence intensity (MFI) of cluster of differentiation 80 (CD80) molecule on B-regs, and the association between assessing the soluble form of lipopolysaccharide (LPS)-binding protein (LBP) and toll-like receptor 4 (TLR4) in serum for T1DM without and with urinary tract infections in comparison to healthy individuals. Materials and Methods: A total of 90 male children, whose ages ranged between 5 and 15 years participated in this study. The frequency of B-cell subsets was measured using flow cytometry and cultivation urine on agar to indicate urinary tract infections (UTIs). The level of human serum LBP and TLR4 was measured using enzyme-linked immunosorbent assay (ELISA) assay. Results: According to the study’s findings, T1DM with UTIs significantly increased CD80 expression on B-regs, whereas T1DM without UTIs only slightly decreased it when compared to the control group. Additionally, it demonstrated that in both groups of T1DM patients, the MFI of CD80 expression on B-reg has significantly decreased. The study also showed that T1DM with UTIs had significantly higher serum levels of TLR4 than other two groups. Conclusions: This study suggests a significant role for costimulation via CD80 molecule that up-regulates on B-regs surface in T1DM progression and innate immune stimulants and modifiers derived from LPS may have important utility in the future to protect against infectious diseases and provide opportunities for immunotherapy to target it.